D44-10bolt compare

Bishop

Bishop

Well-Known Member
Joined
Jul 22, 2006
Location
north of Greensboro
I would like to share some info. and ask some ques. about these two front diffs..

Now I know that all this could be answered by saying "just get a D60". I would do that if they were easy to find and wasn't so expensive. But just compare these two.

My first ques. is: Why is the D44 considered a better diff than a 10 bolt? I have a D44 from a '74 blazer and a 10bolt from a '77 3/4 chevy. My plan was to use the D44. I plan on using 38.5 tires. Now in dismantling both diff I did some comparisons.

D44
-hub spline 19 axle spline 30
-axle thickness 1 5/16
-spline contact surface at diff. 1 1/4
-housing tube 2 3/4
-flat top knuckles
Now I know there is more, like ring gear, pinion size and other
that I don't know at this time.

10bolt
-hub spline 19 axle spline 28
-axle thickness 1 5/16
-spline contact surface at diff. 1 3/8
-housing tube 3
-also thicker spindles, bigger inner bearings
-knuckles aren't flat top
Also, I know there's more...

Now why would Chevy put a 10bolt under a 3/4 ton if it wasn't good?:confused:
Most of the D44s I've seen have been under 1/2 tons.
Now I know there are exceptions.

What I'm getting at is if you had a choice which would you choose and why.
Any other info. about these two is welcomed.

And like I said if I could get a D60 I would.

Thank you, Bishop
 
how much wider is the 10bolt than the44
 
From what I've heard the 2 extra splines you get out of a dana 44 over the 10 bolt (28 vrs 30) is pretty much the real difference maker. All the outer stuff on the two axles is the same thou so its all interchangeable. Not sure on ring gear size. I do know that there were some 30 spline 10 bolts offered honestly I don't know of the difference between the 30 spline 10 bolt and a dana 44.
 
Who said a D44 is better than a 10 bolt? You can see from the stats you listed there's not much difference. You are right about the 28 vs. 30 spline, obviously 30 spline is more desireable, but I think 10 bolts from 88-91 blazer/subs also have 30 spline. A 3/4 ton 10 bolt or dana 44 has 8 lug and bigger brakes but not much difference otherwise. Oh, and axle tube on a 10 bolt is 2 3/4", at least the one from an 88 sub that I had was. The ring gear on both is nearly the same, around 8.5". The biggest problems will be the 19 spline outers and ujoints on both.
 
Seeing Red Again said:
Is it possible to swap in a 30 spline carrier and have some 30 spline shafts cut?
I don't even know if that's even possible just a thought.
Click to expand...
Waste of time and $$ Most 10 bolt/ 44 breakage is stubs, and joints. One is really no better than the other, except there is more aftermarket stuff for a 44 since they were used in more veheicles.

The only thing you need for either one is a good can of turd polish.
 
maddog411 said:
Who said a D44 is better than a 10 bolt? You can see from the stats you listed there's not much difference. You are right about the 28 vs. 30 spline, obviously 30 spline is more desireable, but I think 10 bolts from 88-91 blazer/subs also have 30 spline. A 3/4 ton 10 bolt or dana 44 has 8 lug and bigger brakes but not much difference otherwise. Oh, and axle tube on a 10 bolt is 2 3/4", at least the one from an 88 sub that I had was. The ring gear on both is nearly the same, around 8.5". The biggest problems will be the 19 spline outers and ujoints on both.
Click to expand...

I believe that I've heard more from people stating that they would rather have a D44? Why, I don't know, that's why I wrote this.

Like I stated mine is a '77 3/4, and the tubes are 3".

The spindles from the 10 are bigger on the inside (inner bearing) than the D44. The outer is the same.

Now this is for my application and may not be for every year.

As far as changing splines, yes buying a new carrier and axles would solve that problem.

Again, I know there are better diffs.. Not everyone can afford or need bomb proof parts. Sometimes you have to use what you have.
 
I have a 10bolt
I have 38.5s
It is open
It has held up fine for a couple years.

I also have a D60 I have been building for like 6 months now.

PBB (or maybe ck5, I cant remember) has a great article on the differences.

IMHO there are pros and cons to each,but neither is a 60.
I run mine cuz it was free when I started and it hasnt broke yet, it WILL break(probably on my upcoming tellico trip) and I will then finish my 60....
 
Remember the 44 is a one piece rotor and the 10 is a seperate hub and rotor.
Click to expand...

Both have a separate hub and rotor. I've never seen otherwise.

obviously 30 spline is more desireable
Click to expand...

Don't hold your breath. Yes, a 30 spline 10 bolt was available in the 89-91 K5's and Suburbans, but the increase in spline count marginally increased the size of the shaft. To compensate for this, they machined more material out of the carrier to make the shaft fit, making the carrier weaker than it already was.

Bottom line, the only thing that makes a D44 more desirable than a 10 bolt is the flat top knuckles and the ability to put a lower gear in it (higher numerically). This highest gear a D44 can capacitate is a 5.89. A 10 bolt can only go as high as 5.13.
 
http://www.coloradok5.com/specs.shtml
Don't know if this information is completely accurate, but according to this article on Blazers, the 10 bolt fronts had an axle dia. of 1.28" for both 28 spline and 30 spline versions and the D44 has and axle dia of 1.31" with all being 30 spline. I don't know how the 2 would actually compare strenght wise with those minor differences (if that info is correct).
 
For me, the thing would sway my choice would be gear selection. For the most part, as you noted, the axle specs are very similar. I think there are probably a lot more 44s out there than 10 bolts. My info is that the 10 bolt had factory gear ratios of 2.56:1 through 4.56:1 while the Dana 44 had 2.76:1 through 5:89:1. Being able to regear with 4.88s, 5.13s or lower would be the best reason to choose the 44. If you only needed to run 4.56 and higher gears it would be a toss up.
 
?????

Now why would Chevy put a 10bolt under a 3/4 ton if it wasn't good?:confused:


Maybe the same reason they put independent suspension under the front of a 3/4 ton "heavy duty" truck........ Dunno, doesn't make sense to me.
 
It wasn't a slam on General Motors. They all did it at some point. But...... General Motor is the only one still doing that kind of thing. (ok, this is the slam)
 
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